The invention relates to a luminous display, in particular to a luminous display including OLEDs, or organic light emitting diodes, for controllably emitting light. The invention further relates to a method for controlling a display according to the invention.
OLED pixel cells suffer from degrading performance throughout the display's life due to ageing. Further, the electro-optical properties of the pixel cells can vary across the display screen due to imperfections in the manufacturing process. In order to compensate for this effect, measuring the properties of the pixel cell and adapting the drive signals, in particular for voltage driven OLED pixel cells, is commonly used. Driving OLED pixel cells using a drive voltage rather than a control current allows for faster setting the desired amount of light to be emitted. Measuring the properties of the OLED pixel cell during normal operation, however, requires additional power supply, control and measuring lines, which reduce the effective area through which light is emitted. On the other hand, measuring during specific measurement cycles, e.g. each time when the display is switched on, using the same lines as are used for programming reduces the number of additional lines but does not allow for permanent adaptation of the driving signal.
It is, therefore, desirable to provide a luminous display and a method for controlling the same, which allow for measuring the properties of the display elements during normal operation.